Krunoslav Zmaić

Economic effects of winter wheat fertilization

The winter wheat (variety Zitarka) field trials were set up in the autumn of 2002 and 2003 on silty loam stagnic luvisol at site Donji Miholjac in eastern Croatia. The soil was very acid (pHKCl = 3, 61) with low organic matter content (1, 56%), low P level (102 mg P2O5 kg-1) and low K level (135 mg K2O kg-1). Treatments in the field trials were: 1. no fertilizer, 2. N1P1K1 (80:100:100), 3. N2P1K1 (120:100:100), 4. N2P2K2 (120:200:200), 5. N3P2K2 (160:200:200), 6. N4P2K2 (200:200:200) and 7. N5P2K2 (240:200:200). All those results, as well as results of total income (grain and straw yield × redemption price in 2003 and 2004 + subsidies) and costs were used for profit calculation and determining optimum fertilization ratio. Conducted experiment showed that fertilizer treatments effected yield, straw mass and production profitability. The grain yield increased from 2.94 t ha-1 (control plots) to 7.36 t ha-1 (200 kg N ha-1). The same tendency was approved in cost analysis. The share of fertilizer costs in total production costs were from 20.1 to 26.1% while the fertilizer cost amount per tone of achieved yield raised from 27.1 € for the lowest nitrogen fertilization rate (80 kg N ha-1) to 35.2 € the highest fertilization rate (240 kg N ha-1). Obtained results indicated that the most profitable N levels are from 160 to 200 kg N ha-1.

Effects of early leaf removal on grape yield, chemical characteristics, and antioxidant activity of grape variety Cabernet Sauvignon and wine from eastern Croatia

ABSTRACT The aim of this study was to determine the impact of two different treatments of early defoliation performed before blooming on: grape yield, chemical parameters, polyphenols content, and antioxidant activity of grape and red wine cv. Cabernet Sauvignon from the vineyard located in Ilok, the eastern continental region of Croatia. Two different treatments of leaf removal (LR) were performed: removal of 3 leafs (T1) and 6 leafs (T2) before blooming, together with control (no leaf removal) (T3) during two years (2013 and 2014). Crop yield and average cluster weights per vine were determined. Density, pH and titratable acidity were measured in must, while the total phenols, total anthocyanins and antioxidant activity were measured in the extract of grape skin and produced wine. The analysis of individual anthocyanins in wine was performed by HPLC method. T2 treatment significantly lowered the crop yield and the average cluster weights, and increased total phenols, total anthocyanins, antioxidant activity and most abundant individual anthocyanins in wine. Defoliation did not affect the other chemical parameters in must, grape skin extract and wine. Vintage year is statistically the most significant source of variability for density of must, antioxidant activity in grape skin extract, as well as pH and titratable acidity in wine. This study has showed that the early leaf removal treatment in eastern continental part of Croatia could be used for the production of smaller quantity of high quality Cabernet Sauvignon red wine abundant with anthocyanins.

Profitability of winter wheat production influenced by liming and fertilization

Conducted experiments confirmed that fertilization and liming effected yield and production profitability regardless to considering impact of liming and fertilization as single or aggregate effect. The aggregate impact of liming and fertilization increased yield from 2,7 (control) to 6,7 t ha−1 in 2004 year and single effect of liming or fertilization increased yield from 4,7 to 5,5 or from 2,0 to 6,8 t ha−1, respectively in 2005 year. Cost analysis showes that share of fertilizer in total production costs were from 7% (liming) up to 55% (doubled liming and phosphorus fertilization). Moreover, costs calculation based on computer model for optimal fertilization implicates lower costs and higher profitability of wheat production. The aggregate profit analysis for all three experiments verified significantly lowest profit on control treatments, while any fertilization or liming treatment would increase profit. Optimal fertilization on all three sites would result in doubled profit.

Effects of early leaf removal on volatile compounds concentrations in Cabernet Sauvignon wines from the Ilok vineyards

The aim of this two year study was to evaluate effects of basal leaf removal before blooming on volatile composition of Cabernet Sauvignon wines in the Ilok vineyards (eastern Croatia). During two consecutive vintages (2013, 2014), two different treatments of basal leaf removal were applied: removal of 3 and 6 leaves, and control without leaf removal. Volatile compounds of resulting wines were identified and quantified by gas chromatography coupled with mass spectrometry. Organic acids and higher alcohols remained unaffected by treatments of early defoliation wine, except acetic acid and 2-methyl-6-hepten-1-ol. Early leaf removal was affected on six esters concentration only in the 2014 with different outcome. For compounds unaffected by defoliation, vintage was statistically significant source of variability, as the results of multivariate analysis have confirmed. Defoliation treatments in Cabernet Sauvignon wines from eastern continental part of Croatia should be adjusted to the weather condition in growing season.

Stress indetifiers of disease in Croatian rural economy.

Rural economy in Croatia with your small sized sector of peasant enterprises still stays in the shadow of restructuring of large industrial sector. The slow leading process of privatization, the wandering in the claim the best solution in agricultural development, absence of consensus about key development priorities, as well as common indicators of backwardness, are only part of gray scale of problems which dented the continue pauperization of wide rural area in Croatia. The Croatian government administration late with implementation of new rural policy measures, which are recommended by Council Regulation (EC) No 1257/1999. This act emphasis the balanced development of the countryside alongside the market support measures in the lights of the social and territorial cohesion. It is based on the following principles: recognising the multifunctional role of agriculture, improving competitiveness, ensuring that environmental issues are taken into account, diversifying economic activity, and conserving rural heritage. In the past time new rural policy in Croatia is considered below local and regional development programs, where the LEADER approach take important role. This is result of pre-accession process to EU and new possibilities of using considerable financial support in IPA subsidy program 2007- 2113.

Economic effect of liming in maize, sunflower and winter barley production

Conducted four year experiment confirmed liming effect on yield and production profitability. Since liming investment is quite expensive measure (liming costs participate up to 44% in total cost structure) it is important to know which crop will return invested money more quickly. Conducted liming experiment approved that less profitable crops would result in financial deficit (like maize because of low subsidies and redemption price), while more profitable crops (sunflower and barley) would achieve more respective financial impact of liming. Different approaches to costs analyses showed that liming impact on profit should be analyzed by distribution of liming costs on all seasons in period with liming impact on yield, rather than taking into account liming costs only in production costs of first crop after liming. Regression model for comparing profits and costs during all four seasons determined that the optimal liming dosage on experimental site would be 19 t ha−1.

Economic eficiency of cereal crops production by application of PAM

By applying policy analysis matrix we will determine how efficient the farmers in Croatia in this particular production are and how they deal with negative initiatives in production and marketing. In the Republic of Croatia cereal crops make up for more than two thirds of the total sowed area. Maize is the dominant cereal crop ; it covers 56% of total sowed area. Wheat has a share of 33% of total sowed area and has average production growth of 0, 89% per year (Loncaric et al. 2006). Achieved average yield between 1995 and 2004 for wheat has been 3, 95 t/ha (tons per hectare), for maize 5, 28 t/ha, barley 3 t/ha, oats 2.5 t/ha and rye 2.2 t/ha. The cereal production is characterized by cyclic decrease of growth and fall, which indicates insufficient exploitation of production potential and decrease of competitive ability. Till 1998 cereal crops production, especially wheat production, as the most important bread grain, was surplus thanks to significant customs protection and import ban, which made it possible to keep a high wheat price on the market. Due to greater integration of Croatian agriculture, i.e. entering the WTO and signing the Stabilization and Association Agreement and the Protocol 7, have caused decrease in wheat price and increase in grants.